Protein kinase A modulates an endogenous calcium channel, but not the calcium-activated chloride channel, in Xenopus oocytes

Yan Chen, Jonathan D. Pollock, Yuhuan Wang, Anna A. DePaoli-Roach, Lei Yu

Research output: Contribution to journalArticle

6 Scopus citations


In Xenopus oocytes, Ca2+ influx through an endogenous voltage-gated Ca2+ channel activates a transient outward Cl- current (ICI(Ca)), which is potentiated by cAMP increase. The site of cAMP effect appears to be the Ca2+ channel instead of the Ca2+-activated Cl- channel, because cAMP potentiates the Ba2+ current through the Ca2+ channel in a similar way to the ICl(Ca), and cAMP does not potentiate the Ca2+-dependent CI- current in cells treated with Ca2+ ionophore. Using the catalytic subunit of protein kinase A (PKA) and PKA inhibitors, it was shown that PKA is both necessary and sufficient for the cAMP effect on ICI(Ca). Furthermore, the cAMP/PKA-mediated potentiation of IcI(Ca) was inhibited by both type 1 and type 2A protein phosphatases.

Original languageEnglish (US)
Pages (from-to)191-196
Number of pages6
JournalFEBS Letters
Issue number2
StatePublished - Dec 27 1993



  • Calcium channel
  • Calcium ionophore
  • Phosphatase
  • Protein kinase A
  • Xenopus oocyte

ASJC Scopus subject areas

  • Biochemistry
  • Biophysics
  • Molecular Biology

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